Car for tunnel kilns



EAQSXFE? Aug. 21, 1923.

S. A. MITCHELL CAR FOR TUNNEL KILNS Original Filed April 13, 1920 amvmvtoz Lu 81 I STEPHEN A. MITCHELL, OF NEW CASTLE, PENNSYLVANIA, ASSIGNORT0 AMERICAN DBESSLER TUNNEL KILNS, INC., OF NEW YORK, N. Y., ACORPORATION OF NEW YORK.

CAR FOR TUNNEL KILNS.

Application filed April 18, 1920, Serial To vall whom it may concern: Beit known that I, STEPHEN A. Mrrc citizen of the United States, andresident 0% New Castle, in the county of Lawrence and State ofPennsylvania, have invented certain new and useful Improvements in Carsfor Tunnel Kilns, of which the following isa specification.

My present invention consists in improvements in the means employed fortransport- 2 ing bricks and analogous ware-through continuous tunnelbrick dryingor firing kilns,

' and the object of the invention is to provide a construction whichwill obviate a difiiculty experienced with the transporting meansordinarily employed in such kilns and which arise from the changes inthe shape of bricks or other ware during the heating and drying operons.

T "Evarious' features of novelty which charac erize my invention areointed out with articularity in the claims annexed to and fbrming a partof this specification. For a better understanding of the invention,however, and the advantages pomessed by it reference should be had tothe accompanying drawings and descriptive matter in which I haveillustrated and described a preferred embodiment. of my invention.

Of the drawings;

Fig. 1 is a transverse section of a brick firing kiln with a brickloadedcar therein, the brick being shown in their normal shapes asthe enter,

And Fig. 2 is an elevation of a car loaded with brick of the distortedsha es temporarily acquired in the drying and firing operations.

Fig. 3 is an enlarged view of the brick illustrating in a somewhatexaggerated manner the change in shape which occurs during the earlystages of the drying and firing op erations.

And Fig. 4 is a side elevation of the car.

In the drawings I have illustrated the use of my improved transportingmeans in connection with a continuous tunnel kiln of the well-knownDressler type, the elongated kiln chamber A being provided with trackvrails. on which run the cars D for trans rting the bricks'or likematerial through t e kiln. At the sides of the pathway for the goods arecombustion chambers resting on benches A. The combustion chambers are ofthe general type illustrated in the patent No. 373,504. Benewed May 17,1923.

tageously the platform for the bricks is formed of pier like supports Dextending transversely to the direction of travel of the car andseparated from one another by spaces D to permit the circulation of thekiln atmosphere through the bottom portion of the mass of bricks. Thesechannels are atthe level ofthe bottom openings into the open endedcirculating channels B formed in the walls of the combustion chambers.

The improved car construction shown differs, essentially, from thoseheretofore known in the fact that the upper surface of the brickreceiving platform formed by the upper edges D of the piers D, is not ahorizontal plane surface. but comprises two plane surfaces each inclinedslightly downward from the side edges of the car toward the center. Theamount of this inclination should be sufiicient to more or less exactlycompensate for the tilting or change in in clination of the columns ofbricks stacked on the car which results from the normal changes in brickshape occurring in the passage of the bricks through the kiln whenradiant heat from the flues at first causes the outer portions to shrinkfirst.

While in a kiln of the special type illustrated the brick mass of eachcar is heated throughout with substantial uniformity there is ordinarilyan initial period in the drying operation and another initial period inthe firing operation in whichbricks or analogous material dried andfired in tunnel kilns are subjected to more heat at their sides and endsadjacent the side walls of the kiln than at their sides and endsadjacent the longitudinal center line of the car. This results in atemporary excess contraction of the side or end of a brick adjacent theside wall of the kiln as compared with the contraction of the oppositeside or'end of the brick. The effect of the changes in the shapes ofindividual bricks thus produced is to tilt each column of bricks towardthe side walls of the kiln. It is highly desirable to prevent thistilting action from resulting in an outw|ard inclination of the brickcolumns, as when the brick columns lean outward there is danger of someof the bricks falling off the top of the column or of their contact withthe combustion chambers or other ortions of the kiln structure at thesides 0 the goods pathway. This danger is avoided in accordance with thepresent invention by so inclining the upper edges D of the supports Dthat with the maximum tilting toward the side of the kiln the columns ofbricks will be vertical as shown in Fig. 2, or will still lean slightlyaway from the side of the kiln. ith this inclination to the horizontalof the support edges D the brick columns, when the brick are in theirnormal condition, will be inclined to the vertical as shown in Fig. l.he shaping and arrangement of the com iustion chambers to provide agoods pathway which is wider at its to than at its bottom supplementsthe effect oi the special ari angement of the brick supporting surfacesin avoiding injurious contact between the bricks and kiln cars. It willbe understood that ordinarily the bricks when completely dried and whencompletely fired return substantially to their original rectangularshapes except, of course, that the dried and burned bricks are smallerthan the undried bricks.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. A car for transporting bricks and analogous ware through a tunnelkiln comprising a body portion and pier-like goods supports thereonextendingtransversely to the direction of car travel and spaced apart toprovide channels open at their outer ends and upper edges, said supportshaving their upper edges sloping downwardly from the sides of the cartoward its center.

2. The combination with a tunnel kiln shaped to provide a goods pathwaywider at its top than at its bottom of goods transporting means forminga movable kiln floor which slopes downwardly from its side edges towardits center.

Signed at Saginaw in the county of Saginaw and State of Michigan this9th day of April A. D. 1920.

STEPHEN A. MITCHELL.

